The present invention relates to an improved reverse osmosis water treating device in which the preliminary filtered water produced during pure water making and discharged from the reverse osmosis membrane unit is transferred through a pipeline assembly to a preliminary filtered water-using/water outgoing end (faucet) for frequent non-drinking use so as to avoid waste and save water resources. By means of the great amount of waste water discharged from the water outgoing end, the membrane of the membrane unit is washed and cleaned. Accordingly, the useful life of the membrane is prolonged and the quality of the drinking water is enhanced.
The water from a water supply must first go through filtering, precipitation, chlorination and deodorization before it can then be transferred to a domestic faucet for drinking. Such water contains chemical material and people will smell an alien odor when drinking. In order to eliminate this shortcoming, various kinds of filters have been developed. In these filters, a reverse osmosis watertreating device filters off the impurities contained in the water. Such a device includes a tube connecting unit, a water pump, a preliminary filtering unit, a reverse osmosis membrane unit, a washing switch, a flow limiting valve, a shutting valve, a water reservoir and a pipeline assembly connected between the above units.
During the pure water-making procedure of the reverse osmosis water treating device, the ratio of the drinking pure water to the waste water continuously drained out through the flow limiting valve for maintaining the good filtering ability of the membrane is about 1:4. That is, for making one liter of pure water, about four liters of waste water will be drained out without reuse. However, in fact, the so-called waste water has been filtered through a preliminary filtering device to remove larger alien particles and fine particles or chemical material. Although such water is not drinkable, the water has a quality better than general tap water and can be used in cooking, cleaning or other fields. Therefore, it is wasteful to directly discharge such water. Moreover, the conventional water treating device must be periodically washed by manually activating the washing switch so as to clean off the impurities accumulating in the reverse osmosis membrane unit. This is for ensuring the quality of the water and prolonging the useful life of the membrane. Such procedure is inconvenient and troublesome to the user.
It is therefore a primary object of the present invention to provide an improved reverse osmosis water treating device including a tube connecting unit, a preliminary filtering unit, a membrane unit and pipeline assemblies connecting the above units. In the water treating device, the waste water draining end of the membrane unit is directly connected to a non-drinking water-using end the opening/closing of which is controlled by a switching valve. By the frequent use of the waste water discharged from the non-drinking water-using end, the membrane of the membrane unit is washed and cleaned. Accordingly, water resources are conserved, the useful life of the membrane is prolonged and the quality of the drinking water is enhanced. Moreover, by the frequent washing of the membrane, the membrane maintains a good filtering ability so that the flow limiting valve in the water-making procedure can be omitted or reduced.
It is a further object of the present invention to provide a reverse osmosis water treating device in which two ends of the tube connecting unit have a water incoming end (water source) and a preliminary filtered water-using end (faucet). Two through holes are respectively formed on the tube body near the two ends thereof. A diaphragm is located in the tube body to divide the tube body into two sections. One of the through holes via a first pipeline assembly is connected to the preliminary filtering unit and the reverse osmosis membrane unit. The other through hole via a second pipeline assembly is connected to a waste water draining end of the membrane unit. The preliminary filtered water produced during pure water making procedure and discharged from the waste water draining end of the membrane unit is transferred through the second pipeline assembly to the water outgoing end of the tube connecting unit for non-drinking use.
It is still a further object of the present invention to provide a reverse osmosis water treating device in which, in order to avoid decrement of the amount of the water discharged from the water outgoing end of the tube connecting unit due to a pressure drop, the diaphragm of the tube connecting unit is formed with a passage communicating the two sections with each other. A check valve, which is one-way flowable from the water incoming end to the water outgoing end, is disposed in the passage, whereby the water can directly flow from the water incoming end into the water outgoing end.
It is still a further object of the present invention to provide a reverse osmosis water treating device in which, in order to avoid back-flow due to lower pressure in the pipeline assembly, a check valve which is one-way flowable from the outer side to the inner side is disposed in the through hole of the water outgoing end.
The present invention can be best understood through the following description and accompanying drawings wherein: